scholarly journals WHICH IS THE BEST WAY TO PERFORM THE PHYSIOLOGICAL COST INDEX IN ACTIVE INDIVIDUALS WITH UNILATERAL TRANS-TIBIAL AMPUTATION?

Author(s):  
Stefano Brunelli ◽  
Andrea Sancesario ◽  
Marco Iosa ◽  
Anna Sofia Delussu ◽  
Noemi Gentileschi ◽  
...  

BACKGROUND: Physiological Cost Index (PCI) is a simple method used to estimate energy expenditure during walking. It is based on a ratio between heart rate and self-selected walking speed. Previous studies reported that PCI is reliable in individuals with lower limb amputation but only if there is an important walking impairment. No previous studies have investigated the correlation of PCI with the Energy Cost Walking (ECW) in active individuals with traumatic unilateral trans-tibial amputation, considering that this particular category of amputees has an ECW quite similar to healthy individual without lower limb amputation. Moreover, it is important to determine if PCI is also correlated to ECW in the treadmill test so as to have an alternative to over-ground test. OBJECTIVES: The aim of this study was to evaluate the correlation between PCI and ECW in active individuals with traumatic trans-tibial amputation in different walking conditions. The secondary aim was to evaluate if this correlation permits to determine ECW from PCI values. METHODOLOGY: Ninety traumatic amputees were enrolled. Metabolic data, heart rate and walking speed for the calculation of ECW and for PCI were computed over-ground and on a treadmill with 0% and 12% slopes during a 6-minute walking test. FINDINGS: There is a significant correlation between ECW and PCI walking over-ground (p=0.003; R2=0.10) and on treadmill with 12% slopes (p=0.001; R2=0.11) but there is only a poor to moderate correlation around the trendline. No significant correlation was found walking on treadmill with 0% slope. The Bland-Altman plot analysis suggests that is not possible to evaluate ECW directly from PCI. CONCLUSIONS: PCI is a reliable alternative measure of energy expenditure during walking in active individuals with trans-tibial amputation when performing over-ground or at high intensity effort on treadmill. PCI is therefore useful only for monitoring a within subject assessment. LAYMAN’S ABSTRACT The knowledge of the energy cost of walking in disabled people is important to improve strategies of rehabilitation or fitness training and to develop new prosthetic and orthotic components. The “gold standard” for the evaluation of the energy cost of walking is the oxygen consumption measurement with a metabolimeter, but the testing procedure is expensive and time consuming, hardly practicable in many rehabilitation centers. The Physiological Cost Index (PCI) is an indirect tool that evaluates the oxygen consumption during walking. PCI considers heart rate during walking, in relation to the speed, as an indicator of energy expenditure. The formula is “walking heart rate – resting heart rate /speed”. PCI is widely used in literature but there is not a solid evidence of a direct correlation between PCI and energy cost of walking. In particular, for individuals with unilateral trans-tibial amputation without comorbidities, no previous studies have been conducted about this correlation. It has to be noticed that individuals with unilateral trans-tibial amputation have an energy cost of walking quite similar to healthy people. Previous studies reported that in healthy people such correlation does not exist. For this reason, the aim of this study was to evaluate if and in which walking condition a linear correlation exists between PCI and Energy Cost Walking in individuals with unilateral trans-tibial amputation. Oxygen consumption measurement with a metabolimeter and PCI were computed over-ground and on a treadmill with 0% and 12% slopes during a 6-minute walking test in 90 participants. We have found that PCI is an alternative measure of energy cost of walking when performing over-ground or with high intensity effort on treadmill (12% slope). These findings could be useful when PCI is used for monitoring a fitness training or for evaluation tests. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/32953/25717 How to Cite: Brunelli S, Sancesario A, Iosa M, Delussu A.S, Gentileschi N, Bonanni C, Foti C, Traballesi M. Which is the best way to perform the Physiological Cost Index in active individuals with unilateral trans-tibial amputation? Canadian Prosthetics & Orthotics Journal. Volume2, Issue1, No.5, 2019. https://doi.org/10.33137/cpoj.v2i1.32953. CORRESPONDING AUTHOR: Dr. Stefano Brunelli,Fondazione Santa Lucia, IRCCS, Via Ardeatina 306, 00179 Rome, Italy.ORCID: https://orcid.org/0000-0002-5986-1564Tel. +39 0651501844; Fax +39 0651501919E-MAIL: [email protected]

2015 ◽  
Vol 53 (199) ◽  
pp. 174-179 ◽  
Author(s):  
Binaya SJB Rana ◽  
Matiram Pun

Introduction: Physical activity and energy expenditure can be quantified by measuring heart rate, oxygen uptake and respiratory quotient. The Physiological Cost Index (PCI) proposed by MacGregor is a simple and straightforward method to estimate the energy expenditure index. Here, we aim to estimate the energy expenditure among young Asian population using MacGregor’s equation.  Methods: A total of 50 young randomly selected healthy females performed 50m, 100m and 150m walking test at their self-selected preferred speed. The physiological cost index values for 100 m walk at speeds slower and faster than the preferred speed were also obtained. The physiological cost index during exercise was calculated using MacGregor’s equation considering heart rate and speed of walking over the varying distances.  Results: The PCI values on three different distances are consistent during self selected preferred speed. The PCI estimation on second and third tests for all three distances walked consistently reproducible. However for each distance walked, the first test the PCI was significantly higher than the second and third test values. The PCI values increased significantly when subjects walked either slower (p = 0.02) or faster (p = 0.001) than their normal preferred speed.  Conclusion: The physiological cost index values were similar for varying distances walks. The PCI was the least at the preferred speed of walking and increased when the subjects either walked slower or faster than the preferred speed. The first estimation was higher than subsequent estimations.  Keywords: energy expenditure index; exercise; physiological cost index. | PubMed


Author(s):  
Cindy LaPorte ◽  
Daie Johnson ◽  
Kiersten Koen ◽  
Lena Hardy ◽  
Valda Montgomery

Purpose: The purpose of this study was to investigate the effects of dominant leg, lower leg casting on energy cost during independent ambulation. The Physiological Cost Index, predicted VO2max, and gait speed values of a Quarter-Mile Walk Test, with and without lower leg casting, were utilized to determine energy cost. Methods: Thirty-five subjects who were 23 to 32 years old (mean age 25.37 ± 2.02) performed the Quarter-Mile Walk Test at their comfortable walking speed on two occasions, one with and one without lower leg casting. Resting heart rate, walking heart rate, and time to complete the test were recorded. Physiological Cost Index, predicted VO2max, and gait speed formulas were used to calculate results.Results: Physiological Cost Index increased when walking with the lower leg cast, but was not statistically significant (p=.3939). A statistically significant decrease was seen with predicted VO2max (p< .0001) and gait speed (p< .0001) when walking with a lower leg cast. Conclusions: Predicted VO2max and gait speed decreased when walking with a lower leg cast on the dominant leg. This finding indicates that as subjects altered their self-selected speed, predicted VO2max decreased with gait speed.


1999 ◽  
Vol 11 (3) ◽  
pp. 229-239 ◽  
Author(s):  
Lobo Louie ◽  
Roger G. Eston ◽  
Ann. V. Rowlands ◽  
Kwok Keung Tong ◽  
David K. Ingledew ◽  
...  

This study compared the accuracy of heart rate monitoring, pedometry, and uniaxial and triaxial aecelerometry for estimating oxygen consumption during a range of activities in Hong Kong Chinese boys. Twenty-one boys, aged 8–10 years, walked and ran on a treadmill, played catch, played hopscotch, and sat and crayoned. Heart rate, uniaxial and triaxial accelerometry counts, pedometry counts, and scaled oxygen uptake (SVO2) were measured. All measures correlated significantly with VO2 scaled to body mass−0.75 (SVO2). The best predictor of SVO2 was triaxial accelerometry (R2 = 0.89). Correlations in this study were comparable with those in a previous study that used identical methods on 30 UK boys and girls. These results provide further confirmation that triaxial accelerometry provides the best assessment of energy expenditure and that pedometry offers potential for large population studies.


2017 ◽  
Vol 12 (4) ◽  
pp. 504-513 ◽  
Author(s):  
Charles-Mathieu Lachaume ◽  
François Trudeau ◽  
Jean Lemoyne

The purpose of this study was to investigate the energy expenditure and heart rate responses elicited in elite male midget ice hockey players during small-sided games. Nine players (aged 15.89 ± 0.33 years) participated in the study. Maximal progressive treadmill testing in the laboratory measured the relationship of oxygen consumption ([Formula: see text]) to heart rate before on-ice assessments of heart rate during six different small-sided games: 1v1, 2v2, 2v2 with support player, 3v3 with support player, 3v3 with transitions, and 4v4 with two support players. Heart rate was recorded continuously in each game. 3v3 T small-sided game was the most intense for all four intensity markers. All six small-sided games reached 89% HRmax or more with heart rate peaks in active effort repetition. These findings demonstrate that such small-sided games are considered as high intensity games and are an effective training method for ice hockey players.


Author(s):  
Andrew N. Bosch ◽  
Kirsten C. Flanagan ◽  
Maaike M. Eken ◽  
Adrian Withers ◽  
Jana Burger ◽  
...  

Elliptical trainers and steppers are proposed as useful exercise modalities in the rehabilitation of injured runners due to the reduced stress on muscles and joints when compared to running. This study compared the physiological responses to submaximal running (treadmill) with exercise on the elliptical trainer and stepper devices at three submaximal but identical workloads. Authors had 18 trained runners (male/female: N = 9/9, age: mean ± SD = 23 ± 3 years) complete randomized maximal oxygen consumption tests on all three modalities. Submaximal tests of 3 min were performed at 60%, 70%, and 80% of peak workload individually established for each modality. Breath-by-breath oxygen consumption, heart rate, fuel utilization, and energy expenditure were determined. The value of maximal oxygen consumption was not different between treadmill, elliptical, and stepper (49.3 ± 5.3, 48.0 ± 6.6, and 46.7 ± 6.2 ml·min−1·kg−1, respectively). Both physiological measures (oxygen consumption and heart rate) as well as carbohydrate and fat oxidation differed significantly between the different exercise intensities (60%, 70%, and 80%) but did not differ between the treadmill, elliptical trainer, and stepper. Therefore, the elliptical trainer and stepper are suitable substitutes for running during periods when a reduced running load is required, such as during rehabilitation from running-induced injury.


2022 ◽  
Vol 58 (1) ◽  
pp. 196-198
Author(s):  
S. P. Tripathi ◽  
G. S. Chundawat ◽  
Shashi Gour ◽  
S. P. S. Somvanshi ◽  
Kinjulck C. Singh

The study was undertaken to assess ergonomically efficiency of hanging type wheat graincleaner, carried out in adopted villages under On Farm Testing (OFT) and Front LineDemonstration (FLD) program conducted by KVK, Mandsaur (M.P.). Total Fifteen farmwomen were selected to assess the physiological workload to compare the impact ofimproved technology over conventional practice for hanging type grain cleaner. Physiologicalparameters i.e. HR, energy expenditure, cardiac cost reduction and physiological costreduction etc., were measured during operations. The results revealed that hanging typegrain cleaner has proved proficient on time and output parameters. The average cardiaccost of work was decreased by 82.29 per cent while using hanging type grain cleaner forwheat. Drudgery reduction was found 83.96 per cent and it saved time by 89.10 per centwhen compared to traditional practice. The physiological cost of work and energyexpenditure in terms of heart rate were observed to be lower while performing activitieswith hanging type grain cleaner as compared to the traditional practice.


2021 ◽  
Vol 67 (No. 4) ◽  
pp. 181-189
Author(s):  
Ritesh Ranjan ◽  
Prabhanjan Kumar Pranav

Bund shaping is one of the essential operations in preparing a paddy transplanting field. This operation is undertaken manually by spades in a traditional way as this has not been mechanised thus far. Therefore, this study was conducted to expose this operation by evaluating the economic, as well as physiological, cost involved in the bund shaping. For the economic cost, the study was conducted in nine different districts of Assam (India). The bund length for the estimated area was measured and estimated for one ha of land. The average rate of manual bund shaping was also measured to calculate the cost involved in this operation. Moreover, for the physiological cost, ten experienced subjects were calibrated and measured for their maximum aerobic capacity by sub-maximal exercise in laboratory condition. Furthermore, the heart rate was measured during the manual bund shaping and was then correlated with the calibrated data. It was found that the average required bund shaping length per ha was 3 669 m which was associated with a cost of 2 062.8 rupees. It was found that the bund shaping consumed 76.96% of the maximum volume of the oxygen consumption capacity of the subjects; however, the energy expenditure rate with respect to time and bund length were 7.37 kcal·min<sup>–1</sup> and 4.33 kcal·m<sup>–1</sup>, respectively. Hence, bund shaping in a paddy field comes under a severe workload category which emphasises the need of mechanisation for the bund shaping operation.


1994 ◽  
Vol 18 (2) ◽  
pp. 84-91 ◽  
Author(s):  
R. S. Gailey ◽  
M. A. Wenger ◽  
M. Raya ◽  
N. Kirk ◽  
K. Erbs ◽  
...  

The purpose of this investigation was two-fold: 1) to compare the metabolic cost (VO2), heart rate (HR), and self-selected speed of ambulation of trans-tibial amputees (TTAs) with those of non-amputee subjects; and 2) to determine whether a correlation exists between either stump length or prosthesis mass and the energy cost of ambulation at the self-selected ambulation pace of TTAs. Subjects were thirty-nine healthy male non-vascular TTAs between the ages of 22 and 75 years (mean ± sd = 47 ± 16). All had regularly used their prosthesis for longer than six months and were independent of assistive ambulation devices. Twenty-one healthy non-amputee males aged 27–47 years (31 ± 6) served as controls. Subjects ambulated at a self-selected pace over an indoor course, with steady-state VO2, HR, and ambulation speed averaged across minutes seven, eight and nine of walking. Results showed that HR and VO2 for TTAs were 16% greater, and the ambulation pace 11% slower than the non-amputee controls. Significant correlations were not observed between stump length or prosthesis mass and the energy cost of ambulation. However, when the TTA subject pool was stratified on the basis of long and short stump length, the former sustained significantly lower steady-state VO2 and HR than the latter while walking at comparable pace. These data indicate that stump length may influence the metabolic cost of ambulation in TTAs.


1996 ◽  
Vol 81 (4) ◽  
pp. 1754-1761 ◽  
Author(s):  
Jon K. Moon ◽  
Nancy F. Butte

Moon, Jon K., and Nancy F. Butte. Combined heart rate and activity improve estimates of oxygen consumption and carbon dioxide production rates. J. Appl. Physiol.81(4): 1754–1761, 1996.—Oxygen consumption (V˙o 2) and carbon dioxide production (V˙co 2) rates were measured by electronically recording heart rate (HR) and physical activity (PA). Mean daily V˙o 2 andV˙co 2 measurements by HR and PA were validated in adults ( n = 10 women and 10 men) with room calorimeters. Thirteen linear and nonlinear functions of HR alone and HR combined with PA were tested as models of 24-h V˙o 2 andV˙co 2. Mean sleepV˙o 2 andV˙co 2 were similar to basal metabolic rates and were accurately estimated from HR alone [respective mean errors were −0.2 ± 0.8 (SD) and −0.4 ± 0.6%]. The range of prediction errors for 24-h V˙o 2 andV˙co 2 was smallest for a model that used PA to assign HR for each minute to separate active and inactive curves (V˙o 2, −3.3 ± 3.5%; V˙co 2, −4.6 ± 3%). There were no significant correlations betweenV˙o 2 orV˙co 2 errors and subject age, weight, fat mass, ratio of daily to basal energy expenditure rate, or fitness. V˙o 2,V˙co 2, and energy expenditure recorded for 3 free-living days were 5.6 ± 0.9 ml ⋅ min−1 ⋅ kg−1, 4.7 ± 0.8 ml ⋅ min−1 ⋅ kg−1, and 7.8 ± 1.6 kJ/min, respectively. Combined HR and PA measured 24-h V˙o 2 andV˙co 2 with a precision similar to alternative methods.


2006 ◽  
Vol 291 (3) ◽  
pp. R551-R557 ◽  
Author(s):  
Ingrid Wernstedt ◽  
Amanda Edgley ◽  
Anna Berndtsson ◽  
Jenny Fäldt ◽  
Göran Bergström ◽  
...  

Interleukin-6 (IL-6) deficient (-/-) mice develop mature onset obesity. Pharmacological studies have shown that IL-6 has direct lipolytic effects and when administered centrally increases sympathetic outflow. However, the metabolic functions of endogenous IL-6 are not fully elucidated. We aimed to investigate the effect of IL-6 deficiency with respect to cold exposure and cage-switch stress, that is, situations that normally increase sympathetic outflow. Energy metabolism, core temperature, heart rate, and activity were investigated in young preobese IL-6−/− mice by indirect calorimetry together with telemetry. Baseline measurements and the effect of cage-switch stress were investigated at thermoneutrality (30°C) and at room temperature (20°C). The effect of cold exposure was investigated at 4°C. At 30°C, the basal core temperature was 0.6 ± 0.24°C lower in IL-6−/− compared with wild-type mice, whereas the oxygen consumption did not differ significantly. The respiratory exchange ratio at 20°C was significantly higher and the calculated fat utilization rate was lower in IL-6−/− mice. In response to cage-switch stress, the increase in oxygen consumption at both 30 and 20°C was lower in IL-6−/− than in wild-type mice. The increase in heart rate was lower in IL-6−/− mice at 30°C. At 4°C, both the oxygen consumption and core temperature were lower in IL-6−/− compared with wild-type mice, suggesting a lower cold-induced thermogenesis in IL-6−/− mice. The present results indicate that endogenous IL-6 is of importance for stress- and cold-induced energy expenditure in mice.


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